Radio Astronomy Observation on Distributed Deep Space Radar: A Prototype Experiment

Earth-based deep space radar studies celestial bodies by both transmitting and receiving radio waves, whereas radio telescopes only work passively. On the operational level, radar missions use only short observation times, which leaves a large portion of the time available for astronomical observations. However, the design principles used for radar and radio telescopes differ. Technical challenges are involved in making the instruments required to meet the requirements of these two applications simultaneously. In this study, we have attempted to tune a deep space radar system for use in radio astronomical applications and conducted a successful pulsar observation, thus demonstrating the feasibility of using radar systems, particularly distributed deep space radar, to perform astronomical research. Additionally, given the limited astronomical capacity available within the observed frequency range, this system has the potential to contribute to the long-term monitoring of specific radio sources. This work represents the first successful attempt to use an Earth-based deep space radar system to perform radio astronomy in China. We also discuss the challenges of tuning a built radar system for astronomical observation applications and propose recommendations for the design of future large-scale distributed deep space radar systems with innate astronomical capabilities.